Preference for Choice in Humans: Evaluating Indifference Points using an Adjusting Procedure

Past research with concurrent-chain schedules has shown that both animals and humans tend to prefer initial links associated with more options on the terminal link even when reinforcement schedules are equivalent in both terminal links. More recent research with humans has shown that the degree of preference might be due to a past history of reinforcement (Karsina, 2011), it persists in both positive and negative reinforcement conditions (Rost et al., 2014), and that it decreases when non-common alternatives on the free choice terminal link are of lower value than the alternative common to both terminal links (Rost et al., 2014). Studies in other fields have suggested that there may be an upper limit on the number of options that organisms tend to prefer, but single-subject parametric analyses of this effect has yet to be conducted. Several experiments were conducted in which an adjusting procedure was used to assess relative preference for more options on a free choice link as compared to a fixed number of options on the forced-choice link. The results of these experiments indicated that humans might prefer a larger number of options when they only have access to one option on the forced-choice link, and have a preference for a much lower number of options when they have access to two options on the forced-choice link